Drag the GREEN point on the x-axis in the left window (this point is constrained to the segment from 1 to 5).
See the result of building equilateral triangles on this segment.
The function f(x) is currently defined as f(x) = -(x-1)(x-5).
Use the input line to define a new f(x). Try f(x) = sin(x) or f(x) = sqrt(x)
